Semiconductor packages include various components such as semiconductor dies (chips), support substrates for the dies, leads, electrical connections, heat spreaders, etc. The components are typically covered by a molding compound. Semiconductor packages are rated for a certain temperature range, at the extremes of which delamination can occur between the molding compound and one or more of the package components. Delamination occurs due to the difference in thermal expansion coefficients of the different materials. For example, a copper block included in the package for supporting a die or spreading heat has a higher CTE (coefficient of thermal expansion) than the surrounding molding compound. Repeatedly cycling the temperature down to about −40° C. causes the molding compound to begin separating from the copper block along the interface between the molding compound and the copper block. The gap between the molding compound and the copper block resulting from the delamination provides an open pathway for humidity and other contaminants to reach the semiconductor die and other sensitive components included in the package, resulting in catastrophic failure. Delamination of the molding compound is conventionally addressed by roughening the surface of the components surrounded by the molding compound or using an adhesion promoter. These and other conventional solutions increase the package cost and prove to be ineffective at increasing the operating temperature range of the package by a meaningful amount especially towards lower temperatures.